/*

* Copyright (c) 2006 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:  Flow controller for messages

*

*/

#ifndef CCAMESSAGEFLOWHANDLERPC_H

#define CCAMESSAGEFLOWHANDLERPC_H

//  INCLUDES

#include <e32base.h>

#include "MCAMessageObserver.h"

#include "MCASettingsObserver.h"

#include "MCAMessageFlowHandlerPC.h"

// FORWARD DECLARATIONS

class MCAMessagesReadInterface;

class MCASettings;

class MCAConversationManagerPC;

class MCARecordedChatsPC;

// CLASS DECLARATION

/**

*  Flow controller for messages

*

*  @lib wvuiprocessng.dll

*  @since Series 60 3 dot 2

*/

class CCAMessageFlowHandlerPC : public CTimer, public MCAMessageObserver,

            public MCASettingsObserver, public MCAMessageFlowHandlerPC

    {

    public:

        /**

         * Should we fetch new messages or not

         * @param aFetch ETrue if this chat is in foreground and should

         *               receive messages, EFalse otherwise.

         */

        void FetchMessages( TBool aFetch );

    protected: // Functions from MCAMessageObserver

        /**

         * Handle events.

         * @param aEvent Event to handle.

         * @param aIndex, Index of message which is affected by event.

         */

        void HandleMessageEvent( TMessageEventType aEvent, TInt aIndex );

    protected:  // Functions from CTimer

        /**

         * @see CTimer

         */

        void RunL();

        /**

         * @see CActive

         */

        TInt RunError( TInt aError );

    protected:  // Functions from MCASettingsObserver

        /**

         * Handles setting changes.

         * @param aChangedSettingEnum specifies the changed setting.

         */

        void HandleSettingsChangeL( TInt aChangedSettingEnum );

    private:  // New functions

        /**

         * Get flow control value from settings

         */

        void UpdateTimeIntervalL();

        /**

         * Is opening on going or not.

         * @since Series 60 v3.2

         * @return ETrue if opening on going, EFalse otherwise.

         */

        TBool IsOpening() const;

        /**

         * Corrects the real index to current index of messages.

         * This is needed when opening a chat, because messages

         * are not added to container in additional order.

         * @param aIndex Real index of message in container

         * @return current index of message in container.

         */

        TInt MessageIndexCorrection( TInt aIndex ) const;

    private:

        /**

        * C++ default constructor.

        */

        CCAMessageFlowHandlerPC( MCAMessageContainer& aMessageContainer,

                                 MCAMessagesReadInterface& aReadInterface,

                                 MCASettings& aSettings );

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL( TBool aRecordedChatHandler );

    public:  // Constructors and destructor

        /**

         * Two-phased constructor.

         * @param aMessageContainer Interface to UI side message container

         * @param aReadInterface Message read interface

         * @param aSettings Interface to settings manager

         * @param aRecordedChatHandler Is this handler for recorded chat

         *                             or not.

         */

        static CCAMessageFlowHandlerPC* NewL(

            MCAMessageContainer& aMessageContainer,

            MCAMessagesReadInterface& aReadInterface,

            MCASettings& aSettings,

            TBool aRecordedChatHandler );

        /**

         * Destructor.

         */

        virtual ~CCAMessageFlowHandlerPC();

    private:    // Data

        // Interface for UI side message container

        // Not owned

        MCAMessageContainer& iMessages;

        // Interface for fetching messages

        // Not owned

        MCAMessagesReadInterface& iReadInterface;

        // interface for settings manager

        MCASettings& iSettings;

        // time interval for receiving messages

        TTimeIntervalMicroSeconds32 iTimeInterval;

        // Is chat deleted already

        TBool iChatDeleted;

        // Should we fetch new messages

        TBool iFetchMessages;

        // Index for fetching messages

        TInt iMsgIndex;

        // Initial count for messages

        TInt iInitialMsgCount;

        // Is new message received while opening the chat

        TBool iNewMsgWhileOpening;

        // Flag is read from CR variation in class construction

        // ETrue in releases >= 3.2

        // EFalse in releases < 3.2

        // Set to EFalse if this handler is used to handle

        // recorded chat

        TBool iBgOpeningMode;

        TInt iAddedUnreadMsgs;

        // allow unit tests to access protected member functions

        friend class UT_CCAMessageFlowHandler; // CSI: 36 # see above

    };

#endif      // CCAMESSAGEFLOWHANDLERPC_H

// End of File